112 'the nautilus. 



sharply oblique, the last one strongest, forming a prominent ridge 

 parallel to the canal. The upper outlines of the mouth meet in a 

 sharp angle, but the base has a well defined bifurcation. The whole 

 of the aperture and the edge of the outer lip are heavily coated with 

 enamel of a yellowish tint, and rust stained. Size 3i inches long, 

 and 11 inches wide. Animal without operculum. 

 Dredged in Monterey Bay, California. 



MORE ABOUT UNIO LUTEOLUS AND U. RADIATUS. 



BY GEO. W. DEAN, KENT, OHIO. 



I must admit after reading Mr. Simpson's notes in the December 

 Nautilus that Unto radiatus is too erratic for my abilities. A 

 species that takes on every possible form I apprehend would baffle 

 any expert. 



A specimen exactly like luteolus and wholly unlike radiatus as I 

 know it, although in the Lea collection labelled radiatus with the 

 locality Newton Creek, N. J., would, I fear, get into my collection 

 in the tray with luteolus. 



Locality is certainly important but with me does not overshadow 

 everything else, and labels have told me so many lies that I have 

 not the respect for them that I otherwise should have. With me 

 the shell is the central idea, not the locality or the label. These are 

 usually aids in determining species — not always. 



Mr. Lea named a shell, now found in the Mahoning, JJnio siib- 

 ovatus, though from what locality his types came I do not know. 

 It is now known to be the mature male of U. occidens Lea. The fol- 

 lowing are, I think, all occidens : U. ventricosus Barnes, U. ovatus 

 Say and U. cariosus Say. 



Another Mahoning River shell Mr. Lea named U. kirtlandianus. 

 This is probably a variety of that protean species U. subrotundiis, 

 Lea. 



It is a beautiful shell when young and may very properly retain 

 the name as a variety. 



I am in favor of weeding out the surplus names as fast as possible, 

 but I apprehend that both luteolus and radiatus will remain good 



